Nucleic acids encoding B7-H4, a T cell immunoregulatory molecule

Abstract

The invention provides novel B7-H3 and B7-H4 polypeptides useful for co-stimulating T cells, isolated nucleic acid molecules encoding them, vectors containing the nucleic acid molecules, and cells containing the vectors. Also included are methods of making and using these co-stimulatory polypeptides.

1. An isolated DNA consisting of: (a) a nucleic acid sequence that encodes a polypeptide consisting of an extracellular region comprising a V-like Ig domain or a C-like Ig domain, wherein the nucleic acid sequence hybridizes over its full length, after a wash at 50° C. to 65° C. in a buffer containing 0.2×SSC and 0.1% SDS, to the complement of the nucleotide sequence set forth in SEQ ID NO:6; or
 (b) the complement of the nucleic acid sequence of (a). 
 
     
     
       2. An isolated nucleic acid comprising: (a) a nucleotide sequence that encodes a polypeptide comprising amino acids 34-282 of the amino acid sequence set forth in SEQ ID NO:5; or (b) the complement of the nucleotide sequence of (a). 
     
     
       3. A vector comprising the DNA of  claim 1 . 
     
     
       4. The vector of  claim 3 , wherein the nucleic acid sequence is operably linked to a regulatory element which allows expression of said nucleic acid sequence in a cell. 
     
     
       5. A cell comprising the vector of  claim 3 . 
     
     
       6. A cell comprising the vector of  claim 4 . 
     
     
       7. A method of producing a polypeptide, the method comprising:
 culturing a cell comprising a vector, wherein (a) the vector comprises a nucleic acid sequence that encodes a polypeptide consisting of an extracellular region comprising a V-like Ig domain or a C-like Ig domain, the nucleic acid hybridizing over its full length, after a wash at 50° C. to 65° C. in a buffer containing 0.2×SSC and 0.1% SDS, to the complement of the nucleotide sequence set forth in SEQ ID NO:6, and (b) the nucleic acid sequence is operably linked to a regulatory element which allows expression of the nucleic acid sequence in the cell; and 
 purifying the polypeptide from the culture. 
 
     
     
       8. The nucleic acid of  claim 2 , wherein the polypeptide comprises amino acids 33-282 of the amino acid sequence set forth in SEQ ID NO:5. 
     
     
       9. The nucleic acid of  claim 2 , wherein the polypeptide comprises amino acids 32-282 of the amino acid sequence set forth in SEQ ID NO:5. 
     
     
       10. The nucleic acid of  claim 2 , wherein the polypeptide comprises amino acids 31-282 of the amino acid sequence set forth in SEQ ID NO:5. 
     
     
       11. The nucleic acid of  claim 2 , wherein the polypeptide comprises amino acids 30-282 of the amino acid sequence set forth in SEQ ID NO:5. 
     
     
       12. A nucleic acid molecule encoding a fusion protein, the fusion protein comprising a first domain joined to one or more additional domains, wherein:
 (a) the first domain consists of an extracellular region comprising at least a part of a V-like Ig domain and the nucleic acid segment encoding the extracellular region hybridizes, after a wash at 50° C. to 65° C. in a buffer containing 0.2×SSC and 0.1% SDS, to the complement of the nucleotide sequence set forth in SEQ ID NO:6; and 
 (b) the one or more additional domains each consist of an amino acid sequence that is unrelated to the polypeptide encoded by SEQ ID NO:6. 
 
     
     
       13. The nucleic acid molecule of  claim 12 , wherein the nucleic acid segment encoding the extracellular region hybridizes over it full length, after a wash at 50° C. to 65° C. in a buffer containing 0.2×SSC and 0.1% SDS, to the complement of the portion of the nucleotide sequence set forth in SEQ ID NO:6 that encodes the V-like Ig domain of SEQ ID NO:5. 
     
     
       14. The nucleic acid of  claim 12 , wherein the one or more additional domains comprises all or part of an immunoglobulin constant region. 
     
     
       15. A method of producing a fusion protein, the method comprising:
 culturing a cell comprising a vector, wherein the vector comprises: 
 (I) a nucleic acid sequence that encodes a fusion protein, the fusion protein comprising a first domain joined to one or more additional domains, wherein: (a) the first domain consists of an extracellular region comprising at least a part of a V-like Ig domain and the nucleic acid segment encoding the extracellular region hybridizes, after a wash at 50° C. to 65° C. in a buffer containing 0.2×SSC and 0.1% SDS, to the complement of the nucleotide sequence set forth in SEQ ID NO:6; and (b) the one or more additional domains each consist of an amino acid sequence that is unrelated to the polypeptide encoded by SEQ ID NO:6, and 
 (II) the nucleic acid sequence is operably linked to a regulatory element which allows expression of the nucleic acid sequence in the ceil; 
 and purifying the fusion protein from the culture.